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Bathing water quality
Sanitary control organisation
Advices and recommendations
Water and health

Bathing Water Quality and Human Health


Table of contents



published on 01/08/2008


Amoeba are micro-organisms present in all components of the environment. They thrive in humid areas, particularly warm freshwaters where the temperature is between 25°C and 40°C. Only a few of the free amoeba found in the environment are hazardous to man. One is the species Naegleria fowleri.
The warm waters discharged from industrial facilities, in particular electrical power plants, can foster the development of amoeba. The discharge and environments affected are all subject to special monitoring.
Bathing can entail health risks when the local environment is assumed to contain high amoeba concentrations and when the bather inhales water droplets. The risk results from the concentration of amoeba pathogens in the water. This is particularly true of children, who are a favourite target for amoeba.

Health Impacts

Contamination occurs through inhalation: the amoeba enter the brain through the nasal mucous glands and develop there. The disease caused by Naegleria Fowleri (Nf) is an amibiase that leads to brain inflammation (meningoencephalitis). The most common symptoms are headache, fainting, convulsions, drowsiness and, sometimes, abnormal anxiety. The disease is very rare but may be deadly when a diagnosis is lacking.
Since 1967, a total of only 196 cases of meningoencephalitis have been identified across the world, not all due to bathing in contaminated environments. As of today, no cases have been reported in France. This is likely due to the fact that the concentrations found in the environment were low.